When Justin Mason moved from Ireland to America, he wanted to take his cat - so, as required under the Pet Passport cross-border travel scheme, he had him microchipped.

The Pet Passport scheme, which was introduced in 2004, relies on RFID (radio frequency identification) chips to make it work. Simple, you might think: put a chip in each animal and away you go. But the reality is a dog's dinner, as Mason, a programmer, realised when he got to the US and discovered that vets could not read the cat's chip. To him, it smacked of a badly managed IT project - which, as he discovered, is not far off the mark.

Imagine a company-wide IT scheme where almost no one understands the new technology and its capabilities or weaknesses, where every department makes different decisions on hardware and software, where no one is required to adhere to standards and none of the departmental systems talk to each other. Substitute nations for departments, and you have the present system of pet microchipping.

A bit of Googling later, Mason, author of SpamAssassin, the spam-filter program, discovered why. Europe uses International Standards Organisation (ISO) regulation chips, which operate at a frequency of 132.5 kHz (also known as FDX-B chips), while the US uses an older style, 125 kHz chip (known as FDX-A). Most scanners in the US read only FDX-A chips - though some are unable even to read all the 125kHz chips in the US market.

And in a move that has infuriated organisations such as the American Humane Society, and prompted US federal legislation, chips made by Avid (American Veterinary Identification Devices) are encrypted and, in the US, can't be read by non-Avid scanners unless other companies license the technology.

To make sure customs agents could read his cat's chip to match him to his Pet Passport on return to Europe, Mason bought his own scanner at a cost of some £200. "I didn't want to risk the cat being impounded for six months' quarantine at Heathrow," he sighs.

Database dangers

Not that the headaches end there. A chip is only as dependable as the database it links to. However, there are many databases which often don't share information. Additionally, a foreign chip - which may be only as "foreign" as a standard European ISO chip but in a British dog that gets lost on holiday in Ireland - offers no obvious information regarding its origin.

The anxious owner must rely on officials at a pound or shelter being diligent and hunting down both the nationality of the chip and the database it is linked to. In frustration, European animal welfare groups and vets have set up two services to try to overcome this: petmaxx.org and europetnet.com. Enter a chip number and these will search national databases to try to identify the pet's owner.

So why the mess? From Mason's perspective, it's a classic IT project gone awry: "Because it's at the bleeding edge of technology, no one really understands how to use this stuff."

Finbar Heslin, a vet in the Irish Republic who has worked to try to streamline Irish microchipping standards, says part of the problem is that RFID chips have been developed for a different market. "The idea behind microchipping is excellent. The downside is that you're taking the technologies from the logistics industry and trying to apply them to animals."

Logistics is a huge market for RFID and so there is a greater incentive to adhere to standards. "But with animals, the RFID market is small, and there are no standards, even across Europe," says Heslin.

In both Britain and Ireland, the situation has been what he calls "a free for all", because distributors weren't licensed and cheap, non-ISO chips were sometimes brought in from abroad.

Another problem is the lack of uniformity in database provision, Heslin says. Different information goes into different databases; some time-stamp information every time it is changed, some take only paper-based submissions, some need the registration data supplied by the pet owner, some by vets or shelters.

Chris Laurence, veterinary director for the Dogs Trust, says the UK has worked hard to address these issues. The British Small Animal Veterinary Association has a microchip advisory group that has helped develop standards and the Dog Identification Group (comprising welfare groups, vets and dog wardens, and chaired by Laurence) has worked with chip manufacturers, distributors and inserters to develop a code of practice.

Chips are now tracked from manufacturer to the organisation that placed it in the animal, which means an animal should be traceable even if wrong information is on the database, Laurence says. "The databases are also all accessible by a single point of contact, and that's taken quite a lot of time to agree," he adds.

While everyone in animal welfare says chipping is one of the best things you can do to ensure a lost animal will be returned to you, the overall systems badly need consistency and structure, animal welfare organisations and vets agree.

You might, of course, think that all this applies only to animals, and so isn't worth worrying about. But in Cincinnati, Ohio, a security company, Citywatcher.com, has implanted three staff with RFID chips. US hospitals are getting ready to be able to read them, implanted perhaps in Alzheimer's patients. Mason's experience was with his cat; but will people be next?

What's in a microchip?

Pet microchips contain an RFID tag with its attached antenna and transmitter. The tiny array is encased in a bio-compatible sheath which is generally protein-coated glass that will not be rejected by or irritate the pet. The size of a grain of rice, the chip is injected by a hollow needle into the loose skin between the animal's shoulderblades.

UK standard chips contain a 15-digit number that links to one of three databases operated by the UK's chip distributors: Petlog, AnimalCare, or Avid. When a chipped animal is scanned with a handheld reader, the reader emits a radio signal at the chip's frequency, causing the chip to reflect back a radio signal that sends its data to the reader. After the chip inspects itself to verify that its information is uncorrupted, it sends the 15-digit number which is then checked against the database, and the owner's information in retrieved. Some newer chips contain a biosensor and can also send the animals' temperature.

The Dog Identification Group (DIG) estimates about 2.3 million of the UK's 6.4 million dogs - 36% - have been microchipped. The group's goal is for 75% to be chipped in the next five years.

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